Printing telegraph system and apparatus



Dec. 21, 1937. E. E. KLElNscHMlDT 2,102,899

PRINTING TELEGRAPH SYSTEM AND APPARATUS Filed April 25, 1936 4 Sheets-Sheet 1 es 1 5o\` l a3 t 72' 67 23..,-

11 l 69 85 5taw Il] "l l| 59 'n lli h I 1 M l 1 'A'rToR EY Dec- 21, 1931 E. E. KLEINSCHMIDT 2,102,899

y PRINTING TELEGRPH SYSTEM AND APPARATUS Filed April 25, 1956 4 SheebS--Sheell 2 'Eels m 4 nlA FIG. 2

INVENTOR EDWARD E. KLEINSCHMIDT ATTOR Y Dec. 21, 1937. E. E. KLEINSCHMIDT 2,102,899

PRNTING TELEGRAPH SYSTEM AND APPARATUS Filwed April 25, 1936 4 Sheets-Sheet 3 FIG. 3

INVENTOR EDWARD E. KLEINSCHMIDT ATTOR EY Dec. 21, 1937. EfE. KLEINSCHMIDT PRINTING "IEJEG'lQ/FH SYSTEM l AND*` APPARATUS Filed April' 25, 1956 4'sheets-sheet 4 INVENTQR EDWARD E. KLEINSCHMIDT ATTOR EY Patented Dec. 21, 1937 UNITED STATES PATENT OFFICE aloasss PRINTING TELEGRAPH SYSTEM AND APPARATUS Application April 25, 1936, Serial No. '76,357

27 Claims.

This invention relates to printing telegraph systems and apparatus.

An object of the invention is to provide a remotely controlled printing telegraph machine 5 which may be employed economically in localities where the traffic service is light and where it is feasible to operate the apparatus at relatively slow speeds.

Another object ofthe invention is to provide a simple telegraphic system which is automatic and in which phasing and synchronization of the interconnected printing apparatus is automatically effected cyclically irrespective of the character selecting function of the apparatus at the several stations.

Specically, the printing machine according to the present invention is operable on the step-bystep principle. In these machines the type wheel, star wheel drive ratchet, synchronizing arm, and n the commutator contact arm are all fixed to and rotatable with the same shaft. The star wheel drive or motor magnet is a polar magnet responsive to alternating positive and negative impulses. Normally, the alternate segments of the commutator are impressed with positive and negative current so that when the keys of the transmitter keyboard are unoperated, the circuits are completed alternatively to the polar magnet to oscillate the actuating pawl lever and thus drive the 30 type wheel step by step continuously. However,

when a keylever is depressed, the circuit between this particular keylever and its-corresponding segment on the commutator is broken so that when the commutator arm arrives at and contacts with such segment. the type wheel will be stopped preparatory to effecting the printing operation. The circuit for the printer according tothe present 1nvention provides that when the keylever is depressed and the circuit to the corresponding corn- 0 mutator segment is broken, a printing relay is operated in preparation for -the performance of the printing operation.- which occurs when the keylever is released and the circuit from the keylever to its corresponding segment is again completed, at which' time the printing relay permits the establishment of the energizing circuit to the printing magnet. In other words, printing occurs upon make after break of the keylever contact.

A' feature of the circuit for the step-by-step printer according to this invention is the means for effecting synchronization of the ,interconnected printers once every revolution of the commutator arm, and a further feature resides in the positive stopping of the commutator ann on the synchronizing segment after cessation of message transmission and reception for a predetermined interval of time, for example, a period of ten seconds. In connection with the synchronizing feature, it has been mentioned above that the 6 commutator comprises a series of segments trav- `ersed by a contacting arm. One of these segments is identied as the synchronizing segment. Upon the shaft is fixed a synchronizing arm which is adapted, once each revolution of the shaft, to pass through a pair of contact springs making contact therebetween periodically to complete, with the commutator contacting arm simultaneously in contact with the synchronizing segment, a circuit to eifect phasing of the printers. If one of the way station instruments is out of phase with the central or main control station instrument (which is provided with identical commutator and synchronizing means) its synchroni'zing arm will stop between the pair of synchro- 20 nizing contact springs (with the contacting arm simultaneously on the synchronizing segment) until upon the following revolution of the transmitting synchronizing arm, when it again contacts the pair of synchronizing contacts, all the 25 printers will again be phased, and the succeeding stepping operations will be in unison. A characteristic of the commutator of the printer according to this invention is that the rotational movement of the commutator contacting arm simulates 30 or resembles a start-stop arm, due to the fact that the commutator contact arm steps rapidly from segment to segment until it reaches the synchronizing segment, whereat it is arrested momentarily while the synchronizing function, which is 35 operated over a different circuit from that involving the other segments, is being performed.

A better understanding of the invention may be had from the following description, taken in conjunction with the accompanying drawings, wherein Fig. 1 is a frontelevation view of the combination sending and receiving apparatus according to the present invention;

Fig. 2 is a sectional view taken on line 2-2 of Fig. l;

Fig. 3 is a rear elevational viewvof the printer portion of the apparatus shown in Fig. 1;

Fig. 4 is a sectional view taken' on line 4--4 of Fig- 1; 50

Fig. 5 is a schematic diagram of the electrical circuit at the main control station; and

Fig. 6 is a similar diagram of the electrical circuit at the line station.

Having reference to the accompanying drawings in which like reference characters indicate similar parts throughout, the apparatus according to the present invention, as illustrated in Figs. 1 and 2, comprises a base portion and a printer portion indicated generally by reference characters Il and I2 respectively. The base portion houses the keylevers I3 which carry at their outer ends individual key tops I4 and which are pivotally articulated at their other ends with a common fulcrurn bar |5. Keylevers I3 are operable in front and rear comb or guide members I6 and I1, respectively, and are normally held in their horizontal or clockwise position (as viewed in Fig. 2) by individual springs I8. Carried on each of the keylevers 3 is a contact operating member |8 of non-conducting material which acts, upon the depression of an associated keylever I3 (as indicated by dotted lines in Fig. 2), to open a normally closed contact pair 2| which controls an electrical circuit to eiIect character selection and printing in a manner to be hereinafter described.

The printing unit or portion I2 is mounted on the top plate 22 of the base portion and comprises a front plate portion 23 and a rear supporting member 24 (Fig. 2). A shaft 25 is journalled in portion 23 and member 24 and carries on its left end a type wheel 26 and a star wheel drive ratchet 21. Ratchet 21 is integral with a sleeve member 28 provided with a flange 28. Sleeve member 28 is secured to shaft 25 by meansof a screw 3|, and type wheel 261s adjustably secured to ilange 28 by means of slots 32 and screws 33 (Fig. 1) To the right end of shaft 25 is secured a sleeve 34 carrying a. commutator contact arm 35. Shaft 25 is thus constrained against endwise or axial movement by sleeves 28 and 34 nxed thereon. Positioned coaxially with respect to shaft 25 and mounted upon memberl 24 by screws 36 is a commutator, indicated generally by the reference character 31. Commutator 31 comprises a plurality of peripherally arranged and equally spaced contact members 38 (Fig. 3), clamped between rings of non-conducting mateconiact roller 48 yieldingly carried on a spring 43 secured to the extremity of army 35. Simultaneously with its traversal of the contacts 38, roller 42 also contacts a metal ring 44 which is electrically connected to the signal line wire.

The commutator chronizing contact The springs 45 and 46 are assembled with a pair of rigid spacing members 48 and 48 so disposed as to maintain a distance between the lower extremities of springs 45 and 46 slightly smaller than the diameter of arm 41, so that as arm 41 passes between springs 45 and 46, said springs willbe cammed apart to insure proper electrical contact with the synchronizingarm 41. 45 and 46 and spacing members 48 and 48 are carried on the commutator 31. Arm- 41 is carried by a collar 52 secured to shaft 25 by a set screw 53.

The shaft 25 is given step-by-step rotation through the instrumentality of 'a ratchet drive mechanism embodying the ratchet wheel 21 and an actuating pawl lever 54 (Fig. 1). The pawl arms 55 and 56 of the pawl lever 54 are so disposed with respect to the teeth on ratchet 21 as to cause ratchet 21 to be rotated in a clockwise direction (as viewed in Fig. 1) in a manner disbe traversed by a closed in U. S. Patent No. 386,189. Pawl lever 54 is carried on a pivot 51 in the polar motor magnet assembly 58 and is arranged to oscillate between magnetic poles 58 and 58 thereof in wellknown manner.

A print magnet 6I is carried by a bracket 62 mounted on the back of front plate 23. The armature 63 of magnet 6| is pivoted at'64 and acts to control a bank of contacts 65 (Fig. 3) as well as the printing arm and tape spacing mechanism (Fig. 1). The control oi' the contacts of the contact bank 65 will be described in connection with the electrical circuit shown in Figs. 5 and 6. The pivot shaft 64 is journalled in a boss 66 integral with the front plate 23 (Fig. 4). Carried on the outer end of shaft 64 are an actuating lever 61 and a printing arm 68. The actuating lever 61 is iixed to shaft 64 and is provided with a laterally disposed portion 68 which carries an adjustably positionable striker screw 1|. Screw 1| cooperates with a laterally disposed ange 12 on the printing arm 68. Actuating lever 61 is normally held in its counterclockwise position (as viewed in Fig. 1) by means of a spring 13 shown in Fig. 3, which spring also tends to urge armature 63 to its clockwise position (as viewed in Fig. 3). With this arrangement, magnet 5I when it is energized upon the reception of a printing pulse, will cause armature 63 to rotate sharply in a counterclockwise direction (as viewed in Fig. 3) against the action of spring 13. This movement due to the fact that armature 63 and y actuating lever 61 are iixed to the pivot shaft 64,

will cause the actuating lever 61 also to be rotated sharply in a clockwise in Fig. 1) which, through like rotation to printing arm 68. A platen 14 carried at the extremity of printing arm 68 will be thrown sharply against the periphery of the type wheel 26 to eiect printing on a tape 15 interposed between the platen 14 and type wheel 26. The tape supply is derived from a tape reel 16 carried by the printing unit I2, which tape extends around guide rollers 11 and 18 through a tape guide 18 carried Aby brackets 8| and 82 mounted on front plate 23. Printing arm 68 is operable between a pair of eccentric stop screws 83 and 84 which control the extent of its oscillatory movement. 'I'he printing arm 68 is held against the lower stop 83 by a spring 85 which is secured at one end to the printing arm 68 and at the other end to an adjustable member 86, so that the tension of spring may be adjusted to control the printing impact. With this form of printing arrangement, overthrow printing is obtained; that is, a sharp blow is imparted by actuating lever 61 to printing arm 68 which, due to its inertia, is thrown against the type wheel 26 against the action of spring 85.

The actuating lever 61 also acts through a pawl 81 pivotally carried at its extremity to effect the spacing movement of the tape after printing. Pawl 81 is urged by a spring 88 into engagement with a spacing ratchet 88, s'o that upon each oscillation of actuating lever 61, the ratchet 88 will be rotated a distance equivalent to one tooth thereon to impart, in turn, like motion through a pivot shaft 8| to a spacing roller 82. Coacting with the spacing roller 82 is a gripping roller 83 carried on a spring 84 which, through its gripping action, will impart spacing movement to the tape 15 gripped therebetween. A detent lever 85- urged by a spring 86 acts to prevent spacing ratchet 88 from moving in a reversed direction. The enscrew 1|, will impart direction (as viewed trolled by an eccentric adjusting screw 91.

Electrical circuit In Figs. 5 and 6 are illustrated the electrical circuits at the main control station and line station, respectively. The circuits therein shown are in the condition wherein the keylevers I3 and |3a are unoperated and the commutator arms 35 and 35a.' 'are rotating step-by-step in phase. As thevcontactfroller 42 on commutator arm 35 (Figi 5) steps along the commutator segments 38, circuits of alternate polarity'l will be completed through polar motor magnets 50 and 50a to effect through the pawl actuating levers 54 and 54a the rotation of the type wheel shafts of the interconnected printing machines. For example, as indicated in Fig. 5, a circuit is completed from ground, through battery 98 and one winding of relay 99, through closed contacts 2|, associated commutator segment 38, contact roller 42, commutator ring 44, conductor |0|, contacts |02 and |03 of relaysv |25 and ||5 respectively, through polar motor magn'et 50 (Fig. 5) over conductor |04 and thence over line wire |05, through commutator ring 44a (Fig. 6), roller 42a, segment 38a (corresponding to segment 88), contacts 2|a, conductor |06, through polar motor magnet 50a (Fig. 6), manually operated contact |01 associated with the start key, thence through the winding of print magnet 6|a and ultimately to a ground or other return. polar motor magnets 50 and 50a. at the interconnected stations are operated in response to the stepping or signalling impulses, the print magnets 6| and 6|a being of a slower operating type, will not be operated due to the fact that the stepping impulses are of short duration, the printing impulse being one of much longer duration than the signalling impulses. The circuit path indicated generally at (Fig. 5) functions as a spark quenching shunt around the keylever contacts 2l and commutator segments 38.

When a keylever I3 is depressed at the main control station (Fig. 5), the circuit above described will be opened at contact 2 I, the eiect of which will be to cause the deenergizatlon of relay 99, permitting armature |09 to respond to the action of its spring |0 to close contact The contact arms 35 and 35a will continue to be stepped, unaffected by the opening of the contacts 2| by the operated keylever, until rollers 42 and 42ar reach-the segments 38 and 38a associated with the depressed and corresponding keylevers, whereupon, the polar motor magnets and 50a will cease operating with the type wheels positioned, as hereinafter described, to print the character corresponding to the key operated. The deenergization of relay 99 causes va circuit to be completed from ground through contact and armature |09, over conductor ||2, through contact ||3, over conductor ||4, through winding of printing control relay ||5 to battery H6. Printling control relay ||5 thus is operated, causing upper contact |03 to be open and the lever contact ||1 to close. Also, contacts ||8 and ||9 of relay ||5 will be closed simultaneously, causing relay I5 to be locked up over a circuit from battery i6, through winding of relay ||5, through contact ||8 (now closed), over conductor |2|, through contact |22`to ground. This condition of the circuit which includes conductor |0| and the line wire |05 will exist as long as the keylever |3 is held depressed and the contact 2| remains open. However, when the keylever i3 is released and the Although the associated contact.2| is again closed, the relay 99 will again be operated, opening contacts but inasmuch as relay I5 is now locked up, thev opening of contacts will havewno effect thereon.

The circuit for' transmitting the prolonged printing impulse will extend from battery 98 through winding of relay 99, through contact 2|, segmentV 38, roller42, commutator ring V44, conductor |0v|, through contacts |02 and ||1. through print magnet 6|, thence over line wire |05 to the commutator ring 44a at the remote line station (Fig. 6), through roller 42a, segment 38a, and

contact 2 |a, over conductor |06, through winding' of polar motor magnet 50a, throughcontact |01, and the winding of print magnet 6|a and ultimately to ground. It is observed that the circuit just traced does not include motor magnet 50, and hence when the prolonged printing impulse is transmitted, this motor magnet will be unaffected by theY initial portion of the printing impulse. However, the establishment of this circuit by the printing impulse will cause the polar motor magnet 50a and the printing magnets 6| and Sla to operate, but since the printing magnets are of the slow to operate type, the motor magnet'50a will be the rst to respond (to the initial portion of the prolonged printing impulse) to advance the contact arm` 35a, and hence the type Wheel controlled thereby, one step, and immediately thereafter the print magnets Gland 6|a will have become operative to effect printing at their respective stations. The operation of printing magnet 6| will, through contact bank 65 (including contacts ||3. |23, and |24), affect relay ||5 to-open contact |I1 and close contact |03 in a manner presently described.

The operation of the print magnet 6| (Fig. 5) will cause its contacts ||3 and |23 to be opened and its contact I 24 to be closed. The closing of contact |24 applies ground tothe energizing circuit for relay |25 extending from battery |26, through the winding of relay |25, over conductor |21, through contact |24 to ground. The operation of relay |25 will cause the lower contact |22 to open and the upper contact |28 to close. Simultaneously, contacts |02 and |3| will be opened and contacts |29 and |32 will be closed,.the effects of which will hereinafter appear. The opening of contact k|22 causes the locking circuit for relay ||5 to be broken, thereby Apermitting contact |03 to again be closed and contacts ||8 and I9 to be opened. The closing of contact |03 prepares the circuit for polar motor magnet 50 which shall become operated when contact |02 is again closed. Relay |25 will be locked up by a locking circuit extending from battery |26 through winding of relay |25, thence through contact |28 to ground. The opening of contact |02 interrupted momentarily the printing impulse, and the closing of contact |29 served to maintain relay 99 energized by putting ground on the energizing circuittherefor. This interruption of the printing impulse causes printing magnets 4iii and 6|a to become deenergized, The deenergization of printing magnet 6| causes contacts ||3 and |23 to again close and contact |24 to open. The closing of contact |23 short circuits the locking circuit for relay |25 from battery |28, over conductor |33, through contact |23, over conductor |34, through contact |28 to ground. The locking circuit for |25 will thereupon become broken and the contacts associated with relay |25 will again assume the positions indicated in Fig. 5, wherein contactl |02 is closed. The closing of contact |02 estab- ,lishes an energizing circuit for polar magnet 50 and current is impressed on this circuit of the same polarity as thevimmediately preceding portion of the printing impulse, because contact arm 35 is still restingon the same contact 35 associated with the last operated keylever. Polar magnet 50 will respond to this final portion of the printing impulse, but magnet 50a will not re- `spond (because, as will be recalled, magnet 50a responded to the initial portion of the last preceding portion of the printing impulse which was of the same polarity), thus bringing the magnets 5I and 56a again into phase.

From the foregoing it is observed that in order to compensate for the aforementioned effect of the prolongedl printing impulse, the type wheels rotate in a definite out-of-step relationship whichconsists in arranging the characters on the type wheels (of the stations' shown in Figs. 5 and 6) one character out ofstep. According to this arrangement, a particular character on the type wheel of the line printer (Fig. 6) is one step behind the same character cf the type wheel on the main control printer (Fig. 5), and by the initial portion of the printing impulse, whereby the motor magnet 50a is operated and the motor magnet 50 is not operated, the type wheels are brought into exact step or phase (because the type wheel at station Fig. 6 is stepped ahead one step while the type wheel at station Fig. 5 is not stepped) to print the same character. Then after printing, the ilnal portion of the same impulse,l being transferred to the motor magnet 50 through contacts |62 and I 63, causes the motor magnet 50 to operate to step the type wheel associated therewith one step ahead, which impulse portion (being of the same polarity as the initial portion) will have no eil'ect on the motor magnet 50a, hence bringing the type wheels of the interconnected stations into their predetermined'out-of-step relationship.

' The foregoing sequence of operations occurs each time a keylever I3 is operated or depressed to cause the printing of a character corresponding to the keylever operated. However, as pre- .viously mentioned, a synchronizing function is performed' cyclically, during each rotation of the commutator arm 35, which function will now be described.` Assuming that the roller 42 of commutator arm 35 (Fig. 5)is in contact with the synchronizing'segment |35 of the commutator, the synchronizing arm 41 (Fig. 2) will be in engagement with the pair of synchronizing contacts |36 comprising the contact springs 45 and 46 (Fig. 2). As the roller 42 leaves the segments 30 and passes onto synchronizing segment |35 the energizing circuit for relay 93 is broken, so that the initiation of the synchronizing func- `tion will have the same effect on relay I|5 as when the previously described printing function (initiated by the depression of a key I3) is performed. The deenergization of relay 93 will cause contact to close which will cause ground to be applied to relay ||5 which, when operated, becomeslocked up over a previously described locking circuit, and simultaneously closes contact ||1 to prepare a circuit over conductor |0I, through print magnet 6| and over line wire |05.

The bridging of contacts |36 by synchronizing arm 41 establishes a circuit from ground throimh synchronizing contacts |36, thence through the winding of a slow release synchronizing relay |31, then over conductor |36, through contact |33, over conductor I4 I, to battery |42. The operation of synchronizing relay |31 will effect the closing of its associated contacts |43 and |44. The

closing oi conilct |43 will complete a circuit from battery, |42, rough resistance |45, over conductor m, thrugh Contact m and synchronizing segment |35, over roller 42 and commutator ring 44, conductor |I, through contacts |02 and I |1 (now closed) and winding of printing magnet 6| (Fig. 5) ,over signal line |05, over'commutator ring 44a (Fig. 6), through roller 42a and synchronizing segment |41, over conductors |46 and |49, through a pair of synchronizing contacts (assuming the interconnected stations to be in proper phase, the synchronizing arm, not shown in Fig. 6, will be interposed between the pair of contact springs of synchronizing contact |5I, at the same time that the synchronizing arm will :,ioasoo be interposed between the pair of contact springs ofsynchronizing contact |36, Fig. 5), over conductor |52, through contact-|53 (associated with print magnet 6|a) thence through the winding of print magnet 6|a, ultimately to ground.

Since the synchronizing signal impulse is one of long duration (the same as the printing signal impulse), the print magnet 6|a, which is slow to operate, will become operated, whereupon the contact |53 will be opened and the motor magnet 50a at the station shown in Fig. 6 will be operated by the remaining portion of the synchronizing signal to cause the proper oscillation of pawl actuating lever 54a thereat. It will be observed that the synchronizing impulse is of sufficient duration not only to operate the slow'- operating print magnet F6m but also to operate the polar motor magnet 50a after the shunt circuit |52 has been opened at |53, by the operation of armature 63a. In' a manner similar to that described in connection with the prolonged printing impulse, the relay |25 when it operates acts, by opening its contact |02, to cut oil' or terminate the synchronizing impulse. The synchronizing impulse, like the printing impulse, has caused the printing magnet 6| to operate substantially simultaneously with the operation of magnet 6|a. However, the last or final portion of the synchronizing impulse has caused the motor magnet 50a to operate, while the motor magnet 50 (Fig. 5) has notr yet been operated, thus stepping the arm 35a one step ahead 'of arm 35. But, similar to the effect produced by the prolonged printing impulse, the operation of the printing magnet 6| will effect the restoration of the circuits including relays ||5 and |25 to their normal unenergized condition whereupon contacts |02 and |03 will be closed (as shown in Fig. 5) to establish the circuit for motor magnet 50 which will become energized by an impulse through the last described synchronizing segment, since the roller 42 is still resting on the synchronizing segment A |35.- This impulse will operate motor magnet 50,

but will not operate motor magnet 50a, since the latter was just operated by the synchronizing impulse of the same polarity, thus bringing the synchronizing arms 41 (Fig. 2) again into phase. The operation of the polar motor magnets 50 and 50a at the interconnected stations in this manner causes the commutator arms 35 and 35a at the several stations to be stepped along onto the succeeding commutator segments, whereafter the pawl actuating 4arms 54a will be actuated by the alternations of current impulses from batteries 36 and |42 through the motor magnets 50 and 50a, as previously described. At this time relay 99 will again become energized.

In the event that-the mechanism at the station indicated 4by Fig. 6 becomes out of phase with the station indicated by Fig. 5, the present inventio provides means for automatically synchronizing the stations. When the commutator arms 35 and 35a at the stations shown in Figs. 5 ard 6 respectively are not rotating in synchronism, the commutator arm 35a will rotate up to the synchronizing segment |41 and remain thereat-until the commutator arm 35 arrives at the synchronizing segment |35. It is observed that the synchronizing arm 41 and commutator arm 35 are constrained to rotate together, and when it is stated that the commutator arm is in contactual engagement with the synchronizing segment, it is understood that the synchronizing arm is also in contactual engagement with the synchronizing contacts. Asssuming further that the roller 42a on the commutator arm 35a has reached, and remains at, the synchronizing segment |41, and that the commutator arm 35 is in the position shown, the impulse transmitted over the line wire through keylever contact 2| will be received by the apparatus shown ln Fig. 6 over the synchronizing segment |41, said circuit being completed over conductors |48 and |49, through synchronizing contacts |5|, over conductor |52, through contact |53, and winding of print magnet 6|.a and ultimately to ground. Since print magnet 6|a is slow in operating, the circuit through the motor magnet 50a will be shunted, and the short impulse or impulses transmitted from the station .shown in Fig. 5 will have no eiect upon the motor magnet 50a. However, when the roller 42 of the commutator arm 35 reaches the synchronizing segment |35 thereat, a long synchronizing impulse will be transmitted over the line wire |05, in the manner previously described, whereupon the print magnet Bla will be operated to open the contact |53 and to permit the current to pass through the polar motor magnet 50a, causing the motor magnets 50 and 50a at the respective stations to be operated thereafter with both commutator arms operating in phase.

As previously mentioned, the present invention also provides means for stopping the commutator arm upon the synchronizing segment after a ten second (or other predetermined period) cessation of transmission. This feature is achieved 38. However, when the commutator arm 35 contacts the synchronizing segment |35, the ground |84 associated with contact |44 or relay |31 is substituted for the ground |83 associated with contact |3|.

As is observed from the foregoing description, the energizing circuit for magnet |55 is broken periodically by the opening of contact |3| whenever a keylever I3 is depressed and relay |25 is energized during the establishment of the condition set up by the opening of contact 2| associated with the keylever I3. Thus although magnet 55 tends to pull up its armature |51 against the action of the dash-pot relay |66, this function is interrupted periodically by the opening of contact |3|. However, should no keylevers |3 be operated for a predetermined period (for example, ten seconds), the magnet |55 remains energized, and during that interval, pulls up its armature |51 suiiciently to open contacts |39 and |6| and to close contact |64. During the ten-second interval, however, the synchronizing function may be performed several times, thus causing contact |3| to be opened each time, to remove ground |83 from the energizing circuit for dash-pot relay .i 55. Therefore, to compensate for this possibility and to prevent the relay |55 from becoming deenergized prematurely, ground |84 (associated with the synchronizing relay |31) is applied, during the synchronizing interval, in place of ground |83, thus maintaining relay |55 energized. The energizing circuit for magnet |55, previously described, is broken after the ten-second interval and the following circuit is substituted therefor; namely, from battery 98, over conductor |58, through resistance |59 and winding of magnet |55, through contact |64, over conductor |65, through contact |66 associated with the start key |61, over conductor |68, through contact |69 associated with relay |25, over conductor |1|, through contact |12 (associated with printing relay ||5), to ground. If the commutator arm 35 has not yet reached the synchronizing segment |35, impulses will be transmitted over the line wire |05, through the keylever contacts 2| and contacts |l02 and |03 (in series with the conductor through the polar motor magnets 50 and 50a, since the action of the dash-pot relay |54 oncontacts |39, |6|, and |64 will have no effect upon the polar motor magnets 50 and 50a until the commutator arm 35 has reached the synchronizing segment |35.

When this latter condition is established, the synchronizing contacts |36 (Fig. 5) will have been contacted by the synchronizing arm 41 preparatory to establishing an energizing circuit for the synchronizing relay |31. This energizing circuit will not be established because the dashpot relay |54 has caused the contact |39 to be opened, thus cutting off battery |42 from synchronizing relay |31. Accordingly, contact |43 associated with synchronizing relay |31 will remain open and no synchronizing impulses will be transmitted over line wire |05, and hence polar magnets 50 and 50a will cease to operate.

The passing of the roller 42 on commutator contact arm 35 from the commutator segments 38 onto the synchronizing segment |35 will cause the deenergization of relay 99, which in turn permits armature |09 to respond to the action of spring ||0 to close contact and to apply ground to the previously described energizing circuit for relay ||5. The operation of relay causes contacts ||1,l IIB, and ||9. to be closed. Relay I i5 becomes locked up over its locking circuit extending from battery H6, through Winding of relay ||5, through contact ||8, over conductor |2|, through contact |22 to ground. The closing of contact ||9 causes contact |12 to open, and the ground for magnet |55 previously applied through contact |12 will be removed and the circuit for magnet |55 will extend through contact H9, over conductors |19 and |8|, through winding of print magnet 8|, over line wire |05, and

ultimately to ground. i This is the condition that` exists in the system after a ten second cessation of transmission. The function of resistor |53 is to reduce the current over the last described circuit so as not to operate the print magnets 8| and Gla. A Y

The purpose of the previously 'mentioned cont'act |32 is to prevent the accidental deenergization oi' the dash-pot relay |55 during the 'period of ten-second cessation of transmission. -During this ten second period the dash-pot rela'y is slowly pulling up its armature`|51 to 'ultimately close contact |84-, and also, the synchronizing function is recurring regularly to operate relays H5, 5|, and |25 in the order named, as previously described, to transmit the synchronizing signal impulse. While the contact arm 35 is traversing the contacts 38, ground |83 (associated with contact |3| of relay |25) is applied to the energizing circuit fordash-pot relay |55. When the contact arm 35 reaches the synchronizing segment |35, relay |31 becomes energized, closing contact |44 and applying ground |84 to relay |55, thus momentarily, both grounds |83 and |84 are applied to relay |55, after which relay becomes energized to open contact 3| thereby assuring the continued energization of relay |55. Now, when relay |25 operates, contact |59 will open, thus tending to break the aforedescribed circuit including dash-pot relay |55, contacts |54 and |59, and line wire |85. But, if a synchronizing operation occurs at the instant when contact |54 is closed there might occur, but for contact |32, the accidental deenergization of dash-pot relay |55. Thus, if relay |25 operates substantially at the moment when contact |54 closes (and contact |5| opens), then if it were not for contact |32 (which constitutes, with contact |59, a makebefore-break contact; that is, when relay |25 operates, contact |32 closes before contact |59 opens) the completion of the energizing circuit for relay |55 will not be eiected and hence relay 55 will be deenergized to begin over again its ten-second pull-up. Therefore, it is noted that an overlap of closure of contacts |32 and |59 is essential to insure the continued energization of relay |55 after the ten-second cessation.

The printing apparatuses at all of the interconnected stations will remain in their idle or arrested positions until transmission is again initiated by the operation of the start key |51 to open contact |55 to break the energizing circuit just described for the dash-pot relay magnet |55. 'I'he first function automatically performed after the operation of start key |51, and thereon- Bequent deenergization of relay |55, is the transmission of the synchronizing impulse. The deenergization of magnet |55 causes contacts |39 and |5| to close again and contact |54 to open. The closing of contact |39 completes the previously prepared energizing circuit for synchronizing relay |31 from battery |42, over conductor |4|, through contact |39, over conductor |39, through winding of synchronizing relay |31 and synchronizing contacts |35 to ground. Contact |43 will thereupon close to complete the circuit for the transmission of the synchronizing signal impulse from battery 42, through resistance |45, over conductor |45, through contact |43, segment |35, contact ring 44, over conductor lll, through contact |82, contact ||1 (still closed), through print magnet 8|, thence over signal line |85.

The synchronizing impulse as previously mentioned, acts to operate print magnets 5| and 5|a. The operation of print magnet 5|a causes contact |53 to open and to permit the final portion of the synchronizing impulse to pass through and operate the motor magnet 55a as previously described. Magnet 5| isA operated by the synchronizing impulse to open contacts 'H3 and |25 and to close contact |24. 'Ihe closing of contact |24 applies ground to the previously described energizing circuit for relay 25, which pulls up its armatures and becomes locked up over the locking circuit extending from battery |25, through winding of relay |25, contact |28 to ground. The opening of contact |82 of relay |25 cuts-oil.r or terminates the synchronizing imp'ulse to came, in turn, the deenergization of printing magnets 5| and 5|a. The opening ci' contact |22 breaks the locking circuit for relay I5 and permits contact |83 to close and contacts ||8 and I9 to open. The deenergization of print magnet 5| causes contact ||3 to close to short circuit relay |25, as previously described, thus restoring the contacts associated with relay |25 to their position shown in Fig. 5. The contacts |82 and |83 now being closed, the motor magnet 58 will be operated to be brought into phase with motor magnet 58a by a short impulse (of the same polarity as the synchronizing impulse?, as hereinbefore described, through the synchronizing segment |35; thus initiating the step-by-step movement of the type wheel shaft and associated elements.

The system is now in its normal operating condition in readiness for the operation of a keylever I3 and should a keylever not be operated for a period of ten seconds, the dash-pot relay |54 will again operate to stop the commutator contact arm 35 on the synchronizing segment |35, as previously described.

Printing may also be controlled over the herein described system by the depression of a keylever |3a at one of the line stations, as shown in Fig. 6. Upon' the depression of a keylever 3a, the associated contacts 2|a will be opened, the opening of which will h ave the same effect on relay 99 (Fig. 5) as the opening of a contact 2|. The line current for the entire system is derived from batteries 98 and |42 alternatively.

General operation The printing apparatus according to the present invention is shown in Figs. 1, 2, and 3, with the shaft in its synchronizing position; that is, with the synchronizing arm 41 positioned between the synchronizing contact springs 45 and 45 and the roller 42 of the commutator contact arm 35 contacting the synchronizing segment. 'This condition, as previously mentioned, obtains either when the apparatus is in its unoperated or idle position upon the cessation of transmis- -sion of signals for a period of ten seconds, or at the moment of synchronization during the continuous step-by-step rotation of shaft 25 incident to transmission of step-by-step signals. In this positionthe printing magnet 5|, Fig. l, is unenergized and the armature 53 thereof is in its released position under which condition contacts ||3 and |23 are closed and contact |24 is opened.

Upon the actuation of the start key for example |51 (Fig. 5), contact |58 will be opened to cause signal impulses to be transmitted over the signal line and through the magnet 58 to cause the oscillation of pawl actuating arm 54 to eifect in turn the'rotation of the typewheel shafts step-by-step. Upon the actuation of a keylever I3, the associated pair of contacts 2| will be opened, and when the commutator contact roller 42 reaches the segment corresponding to the keylever depressed polar motor oscillating until the keylever I3 is again released to close-contacts 2|. However, before keylever I3 is released to close the contacts 2 I, conditions will be set up to cause the energization of the printing relay magnet I| 5, as previously described, preparatory to transmitting the prolonged printing impulse simultaneously with the release of keylever I3.

T'he transmission of the prolonged printing impulse will, in the manner previously described, effect the energization of print magnets 6| and 6Ia and thev consequent attraction or operation of armatures 63 and 63a. The operation of armature 63 will cause contact pair |24 to close and the pairs of contacts |I3 and I 23 to open, the effect of which has already been mentioned. The mechanical effect of the operation of the printing armature 63. (and 63a) is through shaft 64, to operate the actuating lever 61 (Fig. 1) to cause printing arm 68 to be operated. The operation of printing arm 68 is effective to throw the platen 14 against the type wheel to effect printing upon the tapev 15. Simultaneously therewith, the spacing mechanism is rendered operative to space the tape, after printing, by causing (through the operation of lever 61), the pawl 81 to rotate the tape stepping ratchet 80 one step. Any suitable inking means may be provided; for'example, the inking roller |13 carried upon arm |14, pivoted at |15, which arm is actuated by a spring |16.

To prevent the stepping of the tape during the transmission of the synchronizing impulse, which impulse energizes the print magnet 6| and tends to operate the armature 63 in the same manner as a printing impulse, a blocking means is provided for the printing arm 68, and hence the contacting lever 61 therefor. This blocking means comprises a lug |11 carried on the type wheel 26 and directed inwardly to cooperate with a vertically extending lug |18 integral with the printing arm 68 (Fig. 2). 'I'hus when the synchronizing arm l1 is in contactual engagement with the synchronizing springs 45 and 46, the vlug |11 is presented over the projection |18 of printing arm 68, so that when the prolonged synchronizing impulse operates print magnet 6|, the printing arm 68 will tend to be thrown toward the type wheel but being blocked by lug |11 this motion will be prevented, and hence spacing pawl 81 will not be moved vertically a sufficient distance to effect the rotation of spacing ratchet 88, thereby preventing spacing of the tape during the performance of the synchronizing function.

Although the invention has been described in connection with va specific form thereof, it will be understood that it has further applications and it is not intended to be limited in scope by the embodiment shown herein for illustration.

What is claimed is:

1. In a step-by-step synchronous printing system including a series of stations, a combination transmitting and receiving apparatus at each.

step while said contacts remain closed, said shaft rotatable under said conditions until checked by the opening of the contacts by its associated key, and means associated with one of said stations effective cyclically irrespective of the character selecting function to synchronize said apparatus.

2.*In a step-by-step synchronous printing system including a series of stations, a combination transmitting and receiving apparatus at each station, each comprising a plurality of character keys, a pair of normally closed contacts associated with each key, a vshaft carrying a type wheel, commutator arm, and synchronizing arm thereon, an electromagnetic device responsive under certain predetermined operating conditions to alternations of current for rotating said shaft step by step while said contacts remain closed, said shaft rotatable under said conditions until checked by the opening of a contact by its associated key, means associated with one of said stations effective cyclically irrespective of the character selecting function to synchronize said apparatus, and means effective upon a cessation of operation of said key levers for a predetermined period to arrest the rotation of the shafts at each station in corresponding synchronizing positions.

3. In a telegraph printer, a shaft, a type wheel,

driving ratchet, synchronizing arm, and commutator arm carried on said shaft, a polar motor magnet responsive to line signals, a driving pawl magnetically associated with said magnet and acting in response to the line signals to effect through said ratchet the progressive rotative movement of said shaft, contacts controlled cyclically by said synchronizing arm, 'a commutator coaxially positioned with respect to said shaft provided with segments adapted to be traversed by said commutator arm, and a synchronizing segment cooperative with said contacts to effect phasing operations.

4. In a combination sending and receiving apparatus, a plurality of keys, normally closed contacts associated with each key, a shaft,` a type wheel, driving ratchet, and commutator arm carried on ,said shaft, a polar motor magnet responsive to line signals, a driving pawl magnetically associated with said magnet and acting in response to the line signals to effect, through said ratchet, the progressive rotative movement of said shaft, a commutator coaxially positioned with respect to said shaft provided with segments adapted to be traversed by said commutator arm, each segment being electrically connected individually to one of said contacts, and

means effective upon the opening of any one of said contacts to establish a condition `to effect printing operations.

5. In a step-by-step synchronous printing system, a plurality of stations comprising a main control station and a plurality of line stations, a line conductor connecting the stations, arotatable shaft at each station, a synchronizing arm carried by said shaft, a pair of synchronizing contacts cooperably related to said arm, means effective when said shafts are rotating non-synchronously for arresting an out-of-step line station shaft with its synchronizing arm in contactual engagement with its associated synchronizing contacts to prepare a synchronizing circuit, and means for establishing said synchronizing circuit to restart said line station shaft in synchronism with the main control station shaft when said main control station shaft reaches a corresponding position.

6. In a step-by-step synchronous printing telegraph system, a plurality of stations inter-connected by telegraph lines, means at one o! said stations for transmitting a synchronizing signal, means at the other stations for responding to the synchronizing signal, and means for causing said one station to undergo normal step-by-step operation until said other stations are conditioned to respond to a synchronizing signal and thereafter until it becomes conditioned to transmit vthe synchronizing signal.

7. In a step-by-step synchronous printing sys-- tem, including a series of stations, a combination transmitting and receiving apparatus at each station, each apparatus having a shaft rotatable therein carrying a type wheel and a synchronizelectromagnetic device responsive to alternations of current for constantly rotating said shaft in a step-by-step manner while said contacts remain closed, said shafts rotatable constantly with said type wheels in a predetermined out-of-phase relationship until checked by the opening of a contact by its associated key, a control circuit, and means effective through said control circuit upon the subsequent closing of said contacts to bring the type wheels at said series of stations in phase during the printing operation and thereafter to reestablish said out-of-phase relationship.

9. In a step-by-step printing system, a line circuit,l a main control printer and a plurality of line printers in said circuit, means for transmitting current reversals over said line circuit, and a motor for each of said printers, said current reversals being the sole source of power for operating the printers and motors.

10. In a signaling system, a line circuit, a main control printer and a plurality of line printers in said circuit, a motor for each printer, means including a sole source of power for transmitting current reversals over said line circuit to operate the printers and motors, and means under the control of any of said printers for operating all of said printers.

11. In a signaling system, a line circuit, a main control station and a lplurality of line stations in said line circuit, combination sending and `receiving apparatus at each of said stations, a motor for each apparatus, means including a sole source oi' power for transmitting current reversals over said line circuit to operate the motors and apparatuses, and means eifective under the control of any one oi' said apparatuses for operating all of said apparatuses.

l2. In a signaling system, a line circuit, a main control station anda plurality of line stations in said line circuit, a printer at each of said stations, a motor for each printer, means including a sole source of power for transmitting current reversals over said line circuit to operate the printers and motors, and means under the control of any of said stations for operating all of said printers. l. y

aioasa 13. In a step-by-step synchronous printing system, a line circuit, a main control station and a plurality of line stations in said circuit, combination printing and receiving apparatus at each of said stations, a motor for each apparatus. means including a sole source of power for transmitting current reversals over said circuit for operating the apparatuses and motors, and means under the control of any of said stations to eect stepping before printing at said line stations and stepping after printing at said main control station.

14. In a signaling system, a line circuit, a main control station and a plurality of line stations in said circuit, telegraph apparatus at each station, a motor for each apparatus, means including a sole source of power for transmitting current reversals over said line circuit for operating the apparatuses and motors, and means eiective cyclically for synchronizing said apparatus, said last recited means effective to arrest the further actuation of the motor of an out-of-phase apparatus for one cycle and to thereafter cause said printer to operate in proper phase.

15. In a step-by-step printing system, a line circuit, a main control station and a plurality of line stations in said circuit, printers at each station, a motor for each printer, means for transmitting current reversals over said line circuit, said current reversals being the sole source of power for operating the printers and motors, and means eiective cycllcally for synchronizing said printers, said means acting to prevent further operation of the motor individual to each out-ofphase printer until said printer is in phase with the main control station printer.

16. In a signaling system, a line circuit, a main control printer and a plurality of line printers, a motor for each printer, means including a sole source of power for transmitting current reversals over said line circuit to operate the printers and motors, means under the control of any oi said printers for operating all of said printers, and means effective under certain predetermined conditions to render said rst recited means ineffective.

17. In a signaling system, a line circuit, a main control station and a plurality of line stations in said circuit, a printer at each of said stations, means including a source of power for transmitting current reversals over said line circuit, means under the control of any of said stations for operating all of said printers, and means comprising a slow-acting instrumentality to render said first recited means ineffective.

18. In a signaling system, a line circuit, a-

main control station and a plurality of line stations in said circuit, a printer at each of said stations, means including a source of power for transmitting current reversals over said line circuit, means under the control of any of said stations for operating all of said printers, and means effective after a predetermined period of inactivity of said last recited means to render said rst recited means ineii'ective.

19. In' a signaling system, a line circuit, a main control station and a plurality oi' line stations connected to said circuit, a printer .at each of said stations, means including a source of power for transmitting current reversals over said line circuit, means under the control of any of said -stations for operating all of said printers, and

dash-pot relay device to render said ilrst recited means ineffective.

20. In a step-by-step printing system, a line circuit, a main control printer and a plurality of line printers connected to said circuit, means for transmitting current reversals over said line circuit, a motor for each of said printers, said current reversals being the sole source of power for operating the printers and motors, and slowacting means to render said first recited means ineffective.

21. In a printing system, a line circuit, a main control printer and a plurality of line printers connected to said circuit, means for transmitting current reversals over said line circuit, a motor for each of said printers, said current reversals being the sole source of power for operating the printers and motors, and a dash-pot relay device to render said iirst recited means ineffective.

22. In a signaling system, a line circuit, a main control printer and a plurality of line printers connected to said circuit, a motor foreach printer, means including a sole source of power for transmitting current reversals over said line circuit to operate the printers and motors, means under the control of any of said printers for operating -all of said printers, and means comprising a slowacting instrumentality to render said first recited means ineifectiv'e.

23, In a step-by-step printing system, a line circuit, a main control printer and a plurality of line printers connected to said circuit, means for transmitting current reversalsover said line circuit, a motor for each of said printers, said current reversals being the sole source of power for operating the lprinters and motors, means under the control of any of said printers for operating )all of said printers, and means effective after a predetermined period of inactivity of said last *f recited means to render said rst recited means ineifective.

24. In a telegraph printer, a shaft, a type wheel, driving ratchet, synchronizing arm, and commutator arm carried on said shaft, a polar motor magnet responsive to line signals, a driving pawl magnetically associated with said magnet and acting in response to the line signals to eifect through said ratchet the progressive rotative movement of said shaft, contacts controlled cycli- .cally by said synchronizing arm, a commutator coaxially positioned with respect to said shaft provided with segments adapted to be traversed by said commutator arm including a synchronizing segment cooperative with said contacts to effect phasing operations, and means effective under certain operating conditions to render said magnet ineffective.

55 25. In a combination sending and receiving ried on said shaft, a polar motor magnet responsive to line signals, a driving pawl magnetically associated with said magnet and acting in response to the line signals to eifect, through said ratchet, the progressive rotative movement of said shaft, a commutator coaxially positioned with respect to said shaft provided with segments to be traversed by said commutator arm, each segment being electrically connected individually to one of said contacts, means effective upon the opening of any one of said contacts to establish a condition to eifect printing operations, and means effective after a predetermined period of inactivity of said last recited means to render said magnet ineifective.

26. Ina step-by-step synchronous printing system including a sexies of stations, a combination transmitting and receiving apparatus at each station, each comprising a plurality of character keys, normally closed contacts associated with' each key, a shaft carrying a type wheel, a commutator contacting arm, and a synchronizing arm thereon, a commutator comprising a series of segments including a synchronizing segment, all traversed by said contacting arm, a pair of synchronizing contacts cooperable with said synchronizing arm, an electro-magnetic device responsive to alternations ,pf current for rotating said shaft in a step-by-step manner while said contacts remain closed, said shaft normally rotatable until checked by the opening of the key controlled contacts by its associated key, and circuit means cooperating cyclically with said synchronizing arm, synchronizing segment, and synchronizing contacts for automatically effecting thek synchronizing function irrespective of the character selecting function.

27. In a step-by-step synchronous printing system, a plurality of stations connected together including a phase-controlling station, a motor at each station, a rotatable shaft in each station controlled by the motor thereat, a synchronizing arm carried by said shaft, means for transmitting current reversals over said line circuit, said current reversals being the sole source of power for operating the printers and motors, means acting when the shafts are rotating out of predetermined phase relation to prevent further operation of the motor individual to each out-of-phase printer until said printer is in phase with the main control printer by arresting the shaft of the out-ofphase printer with its synchronizing arm in a predetermined position, and means for reoperating the motor of the out-of-phase printer for restarting the shaft thereat in proper phase with the shaft at the phase controlling station.

EDWARD E. KLEINSCHMIDT. 

